Abstract： Objective To study the chemical constituents of Heterosmilax yunnanensis. Methods The compound was isolated and repeatedly purified with chromatography and the structure was elucidated by physico-chemical properties and spectral analysis. Results A new compound was isolated and identified. Conclusion This compound is a novel compound with structure of 1, 3, 6, 7-tetrahydroxy-xanthone-3-O-β-D-glucopyranoside, roamed heterosmioside A.